1. Field of the Invention
The present invention relates to a dry etching device for etching by a gas plasma generated inside a vacuum chamber.
2. Description of the Prior Art
As an etching method for etching a surface of a semiconductor substrate, a glass substrate for a liquid crystal display or the like according to predetermined patterns, a wet etching method for etching it by using a liquid (an alkali or acid solvent) is conventionally known. However, recently, a dry etching method by using a gas plasma, wherein a liquid washing step and a drying step performed thereafter can be omitted, and refined patterns can be accurately finished, has widely been utilized. As the dry etching method, it is generally known a chemical dry etching (referred to as CDE) operated a chemical etching mechanism, a reactive ion etching (referred to as RIE) operated a chemical and physical etching mechanism, or a spattering etching operated physical etching mechanism.
In any of the above dry etching methods, in the present state, processing ability of an employed dry etching device has a limit, thereby leaving a problem in view of improvement of productivity. Especially, a demand for enlarging a liquid crystal substrate has recently been increased, but, in the conventional dry etching device, as an object to be etched is larger, the processing ability thereof is decreased. Then, there is a method for enlarging a dry etching device itself so as to proceed the large substrate. However, in this case, a plasma density inside the device is decreased thereby being impossible to etching efficiently. In other words, in any case, it has been difficult to work a large liquid crystal substrate or the like at a time and in large quantities.